BIOL 204 LECTURE EXAM 2 2026 FINAL
ASSESSMENT PAPER BIOLOGICAL SYSTEMS
COMPREHENSIVE QUESTIONS AND ANSWERS
VERIFIED A+
◉ why is blood flow in the heart undirectional. Answer: because
valves prevent backflow, ensuring efficient circulation through
chambers and major vessels
◉ why is it important for coronary arteries to branch off from the
ascending aorta. Answer: they supply oxygen rich blood directly to
the heart muscle, which is vital for maintaining its pumping function
◉ what is pulmonary circulation. Answer: the pathway where
deoxygenated blood is pumped from the right heart to the lungs for
gas exchange, then returns oxygenated to the left heart
◉ into which arteries does the brachiocephalic artery divide.
Answer: right subclavian artery and right common carotid artery
◉ what is the role of sarcomeres in the Frank-starling mechanism.
Answer: sarcomeres stretch as ventricles fill, optimizing actin-
myosin overlap to enhance contraction force
,◉ what might happen if preload becomes excessively high. Answer:
it can overstretch muscle fibers, reducing efficiency and potentially
leading to heart failure
◉ which organs and regions do the subclavian arteries supply with
blood. Answer: upper limbs, neck, thorax
◉ how do preload and afterload interact to influence cardiac output.
Answer: higher preload increases stroke volume, while higher
afterload opposes ejection and reduces stroke vole unless
compensated by stronger contractions of reduced ESV
◉ how would a reduced ejection fraction affect systemic circulation.
Answer: less oxygen rich blood is pumped to the body, potentially
causing fatigue and organ dysfunction
◉ what does HFpEF indicate. Answer: Occurs when EF is normal or
above 50%, but the ventricles have difficulty relaxing and filling with
blood during diastole.
◉ what are the 2 main factors that determine cardiac output.
Answer: heart rate and stroke volume
, ◉ what limits the effectiveness of the frank-starling mechanism.
Answer: overstretching or excessive shortening makes actin-myosin
overlap suboptimal reducing contraction force
◉ what are the functions of the pulmonary veins. Answer:
pulmonary veins transport oxygen rich blood from the lungs back to
the left atrium of the heart
◉ how would a decrease in EDV affect stroke volume. Answer: a
decrease in EDV reduces preload, leading to a lower stroke volume if
ESV remains constant
◉ what is the role of the pulmonary artery. Answer: it carries
deoxygenated blood from the right ventricle to the lungs for
oxygenation
◉ how does heart rate influence cardiac output. Answer: increasing
heart rate increases cardiac output if stroke volume stays constant
◉ how is cardiac output calculated. Answer: CO = HR x SV
◉ what is the frank starling law of the heart. Answer: the heart
increases its force of contraction (and stroke volume) in response to
increased ventricular filling during diastole (higher EDV)
ASSESSMENT PAPER BIOLOGICAL SYSTEMS
COMPREHENSIVE QUESTIONS AND ANSWERS
VERIFIED A+
◉ why is blood flow in the heart undirectional. Answer: because
valves prevent backflow, ensuring efficient circulation through
chambers and major vessels
◉ why is it important for coronary arteries to branch off from the
ascending aorta. Answer: they supply oxygen rich blood directly to
the heart muscle, which is vital for maintaining its pumping function
◉ what is pulmonary circulation. Answer: the pathway where
deoxygenated blood is pumped from the right heart to the lungs for
gas exchange, then returns oxygenated to the left heart
◉ into which arteries does the brachiocephalic artery divide.
Answer: right subclavian artery and right common carotid artery
◉ what is the role of sarcomeres in the Frank-starling mechanism.
Answer: sarcomeres stretch as ventricles fill, optimizing actin-
myosin overlap to enhance contraction force
,◉ what might happen if preload becomes excessively high. Answer:
it can overstretch muscle fibers, reducing efficiency and potentially
leading to heart failure
◉ which organs and regions do the subclavian arteries supply with
blood. Answer: upper limbs, neck, thorax
◉ how do preload and afterload interact to influence cardiac output.
Answer: higher preload increases stroke volume, while higher
afterload opposes ejection and reduces stroke vole unless
compensated by stronger contractions of reduced ESV
◉ how would a reduced ejection fraction affect systemic circulation.
Answer: less oxygen rich blood is pumped to the body, potentially
causing fatigue and organ dysfunction
◉ what does HFpEF indicate. Answer: Occurs when EF is normal or
above 50%, but the ventricles have difficulty relaxing and filling with
blood during diastole.
◉ what are the 2 main factors that determine cardiac output.
Answer: heart rate and stroke volume
, ◉ what limits the effectiveness of the frank-starling mechanism.
Answer: overstretching or excessive shortening makes actin-myosin
overlap suboptimal reducing contraction force
◉ what are the functions of the pulmonary veins. Answer:
pulmonary veins transport oxygen rich blood from the lungs back to
the left atrium of the heart
◉ how would a decrease in EDV affect stroke volume. Answer: a
decrease in EDV reduces preload, leading to a lower stroke volume if
ESV remains constant
◉ what is the role of the pulmonary artery. Answer: it carries
deoxygenated blood from the right ventricle to the lungs for
oxygenation
◉ how does heart rate influence cardiac output. Answer: increasing
heart rate increases cardiac output if stroke volume stays constant
◉ how is cardiac output calculated. Answer: CO = HR x SV
◉ what is the frank starling law of the heart. Answer: the heart
increases its force of contraction (and stroke volume) in response to
increased ventricular filling during diastole (higher EDV)
